Method of and apparatus for refrigerating



Aug. 3, 1937. RANDE'L 2,088,609

METHOD OF AND APPARATUS-FOR REFRIGERATING Filed July. 28, 1936 I Z4 i 2;

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INVENTOR BY Bo FoLKE RANDEL.

QM ATTORNEY Patented Aug. 3, 1937 UNITED STATES PATENT OFFICE METHOD OFAND APPARATUS FOR REFRIGEBATIING Bo Folke Randel, San Diego, Calif.

Application July 28, 1936, Serial No. 93,018

7 Claims. (Cl. 62 -115) (Granted under the. act of March 3, 1833, asamended April 30, 1928; 3'70 0. G. 757) 10 the use of the improvements,the invention consists of the parts and combinations thereof hereinafterset forth and claimed, with the -'understanding that the severalnecessary elements constituting the same may be varied in proportion 15and arrangement without departing from the nature and scope of theinvention, as defined in the appended claims.

In order-t make the invention more clearly understood, there are shownin the accompanying drawing means for carrying the invention into 0practical efiect, without limiting the improvements in their usefulapplication to the particular construction, which, for purposes ofexplanation, have been made the subject of illustration.

The single figure of the accompanying drawing is a diagrammatic view ofan apparatus embodying the invention and capable of carrying out theimproved method.

Referring to the drawing, an apparatus constructed in accordance withthe invention is shown as comprising a receptacle or compression tankIll partially filled with a liquid refrigerant l and containing acooling coil I2. A pump I3 driven by a motor l4 withdraws a portion ofthe refrigerant from the tank 10 through a pipe l5 5 and forces it athigh velocity through a pipe l6 and an expansion nozzle located in aninlet chamber |8 of a Venturi tube I9. This Venturi tube is providedwith the usual restricted portion 20 between the inlet chamber l8 and aflared outlet end 2| which extends into the compression tank l0 andcommunicates therewith above the level of the refrigerant The jet ofrefrigerant issuing from the nozzle ll creates a reduced pressure withinthe inlet cham- 5 ber l8 and the outlet end 22 of a second Venturi Theupper end of the tank l0 communicates through a pipe 30 with the lowerend of a coil 3 I, the other end of which communicates through a pipe 32with an expanding nozzle 33 located within the inlet chamber 25 of theVenturi tube 23. The jet of refrigerant issuing from the nozzle I1 drawsvapors from the outlet end 22 of the Venturi tube 23 and forces theminto the compression tank II) where a part of the vapors will be cooledand condensed by the action of the coil. l2. The uncondensed vapors willpass through the pipe 30,- 0011 3|, and pipe 32 to the expansion nozzle33 which will project them through the Venturi tube 23 into the inletchamber IS. The vapor passing through the coil 3| is preferablysuperheated by means of a suitable source of heat such as a burner 34,the heat from which is confined by a hood 35 surrounding the coil.The-reasonfor heating this vapor is that if a small amount of vaporleaves the tank l0 through the pipe 30, it will be considerablyincreased in volume before it passes to the ejector nozzle 33, thusincreasing its effect. The heat imparted to the vapor is, however, much-less than would be required if the vapor had to be produced byevaporating a liquid and then heating it. The condensing capacity maythus be reduced. The jet issuing from the nozzle 33 will reduce thepressure in the pipe 26 and refrigerating coil 21 which will cause acirculation of the refrigerant.

It has been found in practice that it will require approximately ten totwenty pounds of steam in the jet 33 for each pound of water evaporatedin the tank llL-or say at least fifteen pounds of steam will passthrough the pipe 32 to each pound of vapor passing through the pipe 26from the refrigerating coil 21. Therefore, only 1/15 of the steamissuing from the nozzle 33 will be condensed by the cold refrigerant,and even this may be prevented by heating the vapor passing to thenozzle 33 to a sufiiciently high degree.

While the invention has been described as employing a liquid refrigerantand a vapor, it will be understood that it also contemplates anoncondensable .gas, such as air, for a motive vapor. In such case, theair circulates from the tank I, through the heating coil 3| to theexpansion nozzle 33, and thence through the Venturi tubes 23 and I9 backto the tank "I. Also, it is possible to eliminate the heating coil 3|and pass the vapor directly from'the tank ID to the ejector nozzle 33,but in this case the load on the pump l3 will be increased.

The addition of heat to the vapor, whether refrigerant vapor or anon-condensable gas, will increase the capacity of the apparatus withoutadding too'much load on the pump. Also, there are installations whereinwaste heat may be employed to increase the temperature of the vapor. Forexample, the invention may be employed in air conditioning on motorbuses by utilizing the heat from the exhaust manifold to heat the motivevapor.

While a jet pump is shown and described, the invention includes anyconventional pump, where a liquid in motion is used to transfer a vaporfrom a lower to a higher pressure. Any suitable mediums, suchas water,hydrocarbons, air, etc., may be employed within thecontemplated scope ofthe invention.

Other modifications and changes in the proportions and arrangement ofthe parts and in the mediums employed may be made by those skilled inthe art without departing from the. nature and scope of the invention,as defined in the appended claims.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

I claim:

1. The method of refrigeration comprising imparting motion to a liquidrefrigerant, utilizing the energy in said liquid in motion to compress arefrigerant vapor in a compression space, condensing portions of saidvapor in said compression space and passing said condensate to anevaporating space, passing another portion of said vapor to a heatingspace, heating said vapor and passing said heated vapor through anejector device to produce lowering of the pressure in said evaporatingspace to evaporate refrigerant liquid in said space and passing thecombined vapor back to said compression space.

2. The method of refrigeration comprising exhausting an evaporatingspace containing a refrigerant liquid by the means of a vapor ejector,cooling and liquefying the vapor generated in 7 said evaporating space,returning said condensate to said evaporating space, passing the motivevapor from said ejector through a heating space and back to said ejectorand heating said vapor while passing through said heating space.

3. The method of refrigeration comprising exhausting a refrigeratingspace containing a refrigerant liquid by the means of a vapor ejectorand evaporating a refrigerant, passing vapors from said vapor ejector toa liquid ejector and thence to a compression space, condensingrefrigerant vapor in said compression space, passing the remaining vaporthrough a heater to said vapor ejector and said refrigerant condensateto said refrigerating space.

4. A refrigerating apparatus comprising a compression chamber forcontaining a liquid refrigerant; cooling means communicating with saidcompression tank; an ejector supplied with vapor under pressure fromsaid compression tank for circulating the refrigerant from saidcompression tank, through said cooling means and back to saidcompression tank, and for reducing the pressure in said cooling means tovaporize the refrigerant therein, and means for condensing the vaporizedrefrigerant and for returning it to said compression tank underpressure.

5. A refrigerating apparatus comprising a compression chamber forcontaining a liquid refrigerant; cooling means communicating with saidcompression tank; an ejector supplied with vapor under pressure fromsaid compression tank for circulating the refrigerant from saidcompression tank, through said cooling means and back to saidcompression tank, and for reducing the pressure in said cooling means tovaporize the refrigerant therein; means for condensing the vaporizedrefrigerant and for returning it to said compression tank underpressure, and means for heating the vapor supplied to said ejector toincrease its volume and velocity.

6. A refrigerating apparatus comprising a compression chamber forcontaining a liquid refrig- -erant, cooling means communicating withsaid compression chamber; a vapor ejector communicating with saidcompression chamber and said cooling means for reducing the pressure inthe latter to cause the evaporation of the refrigerant therein; a secondejector communicating with said compression chamber and with theexpansion end of said first mentioned ejector for condensing thevaporized refrigerant and delivering it to said compression chamberunder pressure; and means for conducting a motive vapor from saidcompression chamber to said first mentioned ejector.

7. A refrigerating apparatus comprising a compression chamber forcontaining a liquid refrigerant, cooling means communicating with saidcompression chamber; a vapor ejector communicating with said compressionchamber and said cooling means for reducing the pressure in the latterto cause the evaporation of the refrigerant therein; a second ejectorcommunicat ing with said compression chamber and with the expansion endof said first mentioned ejector for condensing the vaporized refrigerantand delivering it to said compression chamber under pressure; means forconducting a motive vapor from said compression chamber to said firstmentioned ejector, and means for heating the motive vapor prior to itsdelivery to said first mentioned ejector to increase its volume andvelocity.

' BO FOLKE RANDEL.

